Question

I have 2 view controllers AViewController and BViewController as an example. I want to add a UI element in the second BViewController from the first AViewController. I thought I would make this happen through the class method but the UIView is not accessable in the BViewController’s class method when called from AViewController.

Implementation of BViewController
+(void)addThatButton{
UIButton *btn = ……
[self.view addSubview:btn]; //<== ERROR
//[BViewController.view addSubview:btn]; //<== ALSO ERROR
}

Implemention of AViewController
[BViewController addThatButton];

Error message I get is “request for member ‘view’ in something not a structure or union”. How to implememnt what I need in the right way or, in other words, how to access BViewController view from the A class?

Thanks

Answer 1

You need to create a function in BViewController

In BViewController.h

UIButton *btnB;

-(void)passButtonFromA:(UIButton *)btn;

In BViewController.m

-(void)passButtonFromA:(UIButton *)btn{
     btnB = btn;
}

-(void)viewWillAppear:(BOOL)animated{

    [self.view addSubView:btnB];
}

In AViewController.m

 BViewController *bViewController =[[BViewController alloc]initWithNibName:.. ...]; //allocated bViewController using your nib file
 [bViewController passButtonFromA:btnA];
 [self.navigationViewController pushViewController:bViewController animated:YES];